World of Warcraft: Cataclysm will be in stores on December 7, 2010 and the time has come to prep for the official launch by implementing its first major patch. Players can experience many major game and user interface systems updates in the first official patch for the upcoming third expansion, patch 4.0.1.

The new Cataclysm Launcher allows you to stream game data while you play. This will reduce the time you spend downloading, installing, and patching World of Warcraft. We'd like to get your feedback on the toolset and gameplay experience. Please head to the forums here for additional information.

Players can now visit special Reforging NPCs in capital cities located near Enchanting trainers. 40% of any one secondary stat on an item can be allocated to add a new secondary stat to the item. The stat being added cannot already exist on the item. An item cannot have more than one reforged stat at a time, though the Reforging of an item can be undone and changed.

Icecrown Citadel and Ruby Sanctum now use the new Flexible Raid Lock system. This system provides the opportunity for a character to defeat each raid zone’s encounters once a week. A character may now complete the encounters during the week with different raids of either 10 or 25 players.

Any dungeon or raid which awarded these emblems will reward Justice Points instead. Anything below Emblems of Triumph, including badges from The Burning Crusade dungeon and raid content, have been converted into gold and sent to players via the in-game mail system.

Any bosses players defeat that are level-appropriate to them award Justice Points.

All items that previously cost emblems or badges of any type now cost Justice Points.

Higher-tier Valor Points will be awarded to players who kill dungeon and raid bosses in the latest tier of PvE content after the launch of Cataclysm.

Many class talents, spells, and abilities have been overhauled, added, or removed.

All spell and ability tooltips will now display damage averages rather than minimum and maximum damage potential. This feature is on by default but can be changed via the Display settings under User Interface options.

Ammo has been removed from the game.

The character levels at which classes gain new spells and abilities have changed.

Many item and class stats have been changed or removed.

Mastery rating has been added as a new stat which provides unique benefits for characters based on class and talent specialization. Mastery rating does not currently exist on items in the game, however, Reforging can be used to add Mastery rating as a secondary stat to existing items.

Rage has been normalized.

Spells and abilities no longer have multiple ranks and now scale with character level.

Talent trees have been altered. All player talent specializations have been reset, allowing for free re-specialization.

Each specialization has been reduced to a 31-point talent tree.

Players will now get a total of 41 talent points to spend at level 85.

Players will be asked to choose a specialization at level 10. Doing so will result in the unlocking of a spell or ability unique to that specialization, as well as one or more passive bonuses.

Once a talent specialization has been chosen, players may only place points in the primary tree until at least 31 points have been spent there.

The initial announcement regarding these talent tree changes can be found on our Cataclysm forum.

The glyph system has been updated to now feature three different types of glyphs, Prime, Major and Minor glyphs, 3 for each type for a total of 9 slots available at one time. Now glyphs are learned permanently on use, much alike a spell learned from a class trainer. Removing/replacing a glyph you have "activated" from your spellbook now costs 1x Vanishing Powder, for characters lev. 80 or lower, while for characters lev. 81 or higher will require 1x Dust of Disappearance for each glyph you want to remove/replace. Many class glyphs have been added, altered, or moved to different glyph types.

The Social Icon from the central menu bar has been moved to chat window.

Spell Alerts have been added to notify players when procs on select spells and abilities occur. A visual notification will display around the character and the activated ability will be highlighted on the action bar.

The Arena Teams pane has been improved.

The Character pane has been redesigned. Character stats can now be shown or hidden via the Show All Details/Hide All Details button on the bottom left. When shown, all character stats will be visible in a window to the right of the pane. Stat sections can be reorganized by clicking and dragging them up or down the pane.

The Professions panes now have more filtering and search functionality, as well as buttons to easily link recipes in the chat frame.

A Professions screen has been added to the Spellbook to better display the details of a character's primary and secondary professions.

Many of the yellow System Messages that would display in the chat frame when leveling up have been removed.

New text animations now alert players as they level up, also providing information on when new talents, spells and abilities are available.

Professions and Class Trainers windows have been altered to more clearly display available and upcoming purchases.

New Raid frames are now available. They can also be used in place of the standard 5-player party interface via the User Interface options.

The Spellbook interface has been improved for greater ease-of-use and visual appeal.